It is known to provide air bag modules with tethers that may be released for controlling the volume and shape of an inflated air bag. U.S. Pat. No. 6,616,184, which is assigned to the assignee of the present invention, discloses an apparatus in which a control module is responsive to signals from occupant condition signals for selectively releasing tethers to control the volume and shape of an inflated air bag.
It is also known to provide air bag modules with vent openings through which inflation fluid may be discharged. When an occupant of a vehicle is positioned in a location such that an air bag will contact the occupant while the air bag is still being inflated, the vent openings enable inflation fluid to be discharged from the air bag to atmosphere. The discharge of inflation fluid through the vent openings reduces the contact force between the inflating air bag and the occupant.
Unites States Patent Application Publication No. 2004/0051285 A1, which is assigned to the assignee of the present invention, discloses an air bag module having a support member that includes vent openings through which inflation fluid may flow. Each vent opening of the air bag module has an associated vent member. A tether connects each vent member to an outer panel of the air bag. When the air bag inflates beyond a predetermined distance relative to the support member, the tethers close the vent members to reduce the flow of inflation fluid through the vent openings.